From patchwork Thu Feb 16 09:09:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Herrenschmidt X-Patchwork-Id: 9576731 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 187EB600F6 for ; Thu, 16 Feb 2017 09:42:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0DDEE2850F for ; Thu, 16 Feb 2017 09:42:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0153A28583; Thu, 16 Feb 2017 09:42:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 43E822850F for ; Thu, 16 Feb 2017 09:42:43 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A63766EA72; Thu, 16 Feb 2017 09:42:41 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4161C6EA76 for ; Thu, 16 Feb 2017 09:42:39 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.13.8) with ESMTP id v1G991De000424; Thu, 16 Feb 2017 03:09:02 -0600 Message-ID: <1487236140.23576.66.camel@kernel.crashing.org> Subject: [PATCH 1/2] drm/ast: Support reading configuration values From: Benjamin Herrenschmidt To: dri-devel@lists.freedesktop.org Date: Thu, 16 Feb 2017 20:09:00 +1100 X-Mailer: Evolution 3.22.4 (3.22.4-2.fc25) Mime-Version: 1.0 Cc: airlied@redhat.com, eich@suse.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Russell Currey The ast driver configures a window to enable access into BMC memory space in order to read some configuration registers. If this window is disabled, which it can be from the BMC side, the ast driver can't function. Closing this window is a necessity for security if a machine's host side and BMC side are controlled by different parties; i.e. a cloud provider offering machines "bare metal". A recent patch from Aspeed tries to detect whether that window is enabled and uses default values if not. Unfortunately this won't work on systems such as POWER machines that have strong PCIe error handling as the attempt at detection will cause a PCIe abort if the window is closed. To work around this, enable reading these configuration values from the device tree instead of through the window into BMC memory if the corresponding DT properties are available. If not, the driver defaults to the existing test which i cleaned up a little bit. Signed-off-by: Russell Currey Signed-off-by: Benjamin Herrenschmidt --- v2. [BenH] - Reworked on top of Aspeed P2A patch - Cleanup overall detection via a "config_mode" and log the selected mode for diagnostics purposes - Add a property for the SCU straps --- drivers/gpu/drm/ast/ast_drv.h | 6 +- drivers/gpu/drm/ast/ast_main.c | 208 ++++++++++++++++++++++++----------------- drivers/gpu/drm/ast/ast_post.c | 7 +- 3 files changed, 127 insertions(+), 94 deletions(-) diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h index 7abda94..3bedcf7 100644 --- a/drivers/gpu/drm/ast/ast_drv.h +++ b/drivers/gpu/drm/ast/ast_drv.h @@ -113,7 +113,11 @@ struct ast_private { struct ttm_bo_kmap_obj cache_kmap; int next_cursor; bool support_wide_screen; - bool DisableP2A; + enum { + ast_use_p2a, + ast_use_dt, + ast_use_defaults + } config_mode; enum ast_tx_chip tx_chip_type; u8 dp501_maxclk; diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c index 533e762..d42a4f5 100644 --- a/drivers/gpu/drm/ast/ast_main.c +++ b/drivers/gpu/drm/ast/ast_main.c @@ -65,10 +65,43 @@ uint8_t ast_get_index_reg_mask(struct ast_private *ast, static int ast_detect_chip(struct drm_device *dev, bool *need_post) { + struct device_node *np = dev->pdev->dev.of_node; struct ast_private *ast = dev->dev_private; - uint32_t data, jreg; + uint32_t data, jreg, scu_rev; ast_open_key(ast); + + /* Check if we have device-tree properties */ + if (np && !of_property_read_u32(np, "ast,scu-revision-id", &scu_rev)) { + /* We do, disable P2A access */ + ast->config_mode = ast_use_dt; + DRM_INFO("Using device-tree for configuration\n"); + } else { + /* + * Check if P2A access works. This will trigger a PCIe abort + * if it doesn't so it's not recommended on platforms where + * this is a fatal error. Those should use the device-tree + * or Aspeed should come up with a different mechanism. + */ + data = ast_read32(ast, 0xf004); + if (data == 0xFFFFFFFF) { + ast->config_mode = ast_use_defaults; + scu_rev = 0xffffffff; + DRM_INFO("P2A bridge disabled, using default" + " configuration\n"); + } else { + /* P2A works, grab silicon revision */ + ast->config_mode = ast_use_p2a; + + DRM_INFO("Using P2A bridge for configuration\n"); + + /* Read SCU7c (silicon revision register) */ + ast_write32(ast, 0xf004, 0x1e6e0000); + ast_write32(ast, 0xf000, 0x1); + scu_rev = ast_read32(ast, 0x1207c); + } + } + if (dev->pdev->device == PCI_CHIP_AST1180) { ast->chip = AST1100; DRM_INFO("AST 1180 detected\n"); @@ -80,12 +113,7 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post) ast->chip = AST2300; DRM_INFO("AST 2300 detected\n"); } else if (dev->pdev->revision >= 0x10) { - uint32_t data; - ast_write32(ast, 0xf004, 0x1e6e0000); - ast_write32(ast, 0xf000, 0x1); - - data = ast_read32(ast, 0x1207c); - switch (data & 0x0300) { + switch (scu_rev & 0x0300) { case 0x0200: ast->chip = AST1100; DRM_INFO("AST 1100 detected\n"); @@ -124,12 +152,6 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post) } else *need_post = false; - /* Check P2A Access */ - ast->DisableP2A = true; - data = ast_read32(ast, 0xf004); - if (data != 0xFFFFFFFF) - ast->DisableP2A = false; - /* Check if we support wide screen */ switch (ast->chip) { case AST1180: @@ -146,17 +168,12 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post) ast->support_wide_screen = true; else { ast->support_wide_screen = false; - if (ast->DisableP2A == false) { - /* Read SCU7c (silicon revision register) */ - ast_write32(ast, 0xf004, 0x1e6e0000); - ast_write32(ast, 0xf000, 0x1); - data = ast_read32(ast, 0x1207c); - data &= 0x300; - if (ast->chip == AST2300 && data == 0x0) /* ast1300 */ - ast->support_wide_screen = true; - if (ast->chip == AST2400 && data == 0x100) /* ast1400 */ - ast->support_wide_screen = true; - } + if (ast->chip == AST2300 && + (scu_rev & 0x300) == 0x0) /* ast1300 */ + ast->support_wide_screen = true; + if (ast->chip == AST2400 && + (scu_rev & 0x300) == 0x100) /* ast1400 */ + ast->support_wide_screen = true; } break; } @@ -220,85 +237,100 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post) static int ast_get_dram_info(struct drm_device *dev) { + struct device_node *np = dev->pdev->dev.of_node; struct ast_private *ast = dev->dev_private; - uint32_t data, data2; - uint32_t denum, num, div, ref_pll; + uint32_t mcr_cfg, mcr_scu_mpll, mcr_scu_strap; + uint32_t denum, num, div, ref_pll, dsel; - if (ast->DisableP2A) - { + switch(ast->config_mode) { + case ast_use_defaults: ast->dram_bus_width = 16; ast->dram_type = AST_DRAM_1Gx16; ast->mclk = 396; - } - else - { + return 0; + case ast_use_dt: + /* + * If some properties are missing, use reasonable + * defaults for AST2400 + */ + if (of_property_read_u32(np, "ast,mcr-configuration", &mcr_cfg)) + mcr_cfg = 0x00000577; + if (of_property_read_u32(np, "ast,ast,mcr-scu-mpll", + &mcr_scu_mpll)) + mcr_scu_mpll = 0x000050C0; + if (of_property_read_u32(np, "ast,ast,mcr-scu-strap", + &mcr_scu_strap)) + mcr_scu_strap = 0; + break; + case ast_use_p2a: ast_write32(ast, 0xf004, 0x1e6e0000); ast_write32(ast, 0xf000, 0x1); - data = ast_read32(ast, 0x10004); - - if (data & 0x40) - ast->dram_bus_width = 16; - else - ast->dram_bus_width = 32; + mcr_cfg = ast_read32(ast, 0x10004); + mcr_scu_mpll = ast_read32(ast, 0x10120); + mcr_scu_strap = ast_read32(ast, 0x10170); + break; + } - if (ast->chip == AST2300 || ast->chip == AST2400) { - switch (data & 0x03) { - case 0: - ast->dram_type = AST_DRAM_512Mx16; - break; - default: - case 1: - ast->dram_type = AST_DRAM_1Gx16; - break; - case 2: - ast->dram_type = AST_DRAM_2Gx16; - break; - case 3: - ast->dram_type = AST_DRAM_4Gx16; - break; - } - } else { - switch (data & 0x0c) { - case 0: - case 4: - ast->dram_type = AST_DRAM_512Mx16; - break; - case 8: - if (data & 0x40) - ast->dram_type = AST_DRAM_1Gx16; - else - ast->dram_type = AST_DRAM_512Mx32; - break; - case 0xc: - ast->dram_type = AST_DRAM_1Gx32; - break; - } - } + if (mcr_cfg & 0x40) + ast->dram_bus_width = 16; + else + ast->dram_bus_width = 32; - data = ast_read32(ast, 0x10120); - data2 = ast_read32(ast, 0x10170); - if (data2 & 0x2000) - ref_pll = 14318; - else - ref_pll = 12000; - - denum = data & 0x1f; - num = (data & 0x3fe0) >> 5; - data = (data & 0xc000) >> 14; - switch (data) { - case 3: - div = 0x4; + if (ast->chip == AST2300 || ast->chip == AST2400) { + switch (mcr_cfg & 0x03) { + case 0: + ast->dram_type = AST_DRAM_512Mx16; break; - case 2: + default: case 1: - div = 0x2; + ast->dram_type = AST_DRAM_1Gx16; break; - default: - div = 0x1; + case 2: + ast->dram_type = AST_DRAM_2Gx16; + break; + case 3: + ast->dram_type = AST_DRAM_4Gx16; + break; + } + } else { + switch (mcr_cfg & 0x0c) { + case 0: + case 4: + ast->dram_type = AST_DRAM_512Mx16; + break; + case 8: + if (mcr_cfg & 0x40) + ast->dram_type = AST_DRAM_1Gx16; + else + ast->dram_type = AST_DRAM_512Mx32; + break; + case 0xc: + ast->dram_type = AST_DRAM_1Gx32; break; } - ast->mclk = ref_pll * (num + 2) / (denum + 2) * (div * 1000); } + + if (mcr_scu_strap & 0x2000) + ref_pll = 14318; + else + ref_pll = 12000; + + denum = mcr_scu_mpll & 0x1f; + num = (mcr_scu_mpll & 0x3fe0) >> 5; + dsel = (mcr_scu_mpll & 0xc000) >> 14; + switch (dsel) { + case 3: + div = 0x4; + break; + case 2: + case 1: + div = 0x2; + break; + default: + div = 0x1; + break; + } + ast->mclk = ref_pll * (num + 2) / (denum + 2) * (div * 1000); return 0; } diff --git a/drivers/gpu/drm/ast/ast_post.c b/drivers/gpu/drm/ast/ast_post.c index 5331ee1..7197635 100644 --- a/drivers/gpu/drm/ast/ast_post.c +++ b/drivers/gpu/drm/ast/ast_post.c @@ -379,17 +379,14 @@ void ast_post_gpu(struct drm_device *dev) ast_open_key(ast); ast_set_def_ext_reg(dev); - if (ast->DisableP2A == false) - { + if (ast->config_mode == ast_use_p2a) { if (ast->chip == AST2300 || ast->chip == AST2400) ast_init_dram_2300(dev); else ast_init_dram_reg(dev); ast_init_3rdtx(dev); - } - else - { + } else { if (ast->tx_chip_type != AST_TX_NONE) ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa3, 0xcf, 0x80); /* Enable DVO */ }